Zooniverse is a collection of web-based citizen science projects, and Chimp & See is listed among the projects. It is the only one I know of that focuses specifically on primates. However there are other projects that include primates in the collections of animals they are interested in. AmazonCam Tambopata has options for identifying 8 monkeys. Snapshot Serengeti has options for vervets and baboons.

Zooniverse: https://www.zooniverse.org/projects?status=live

AmazonCam: https://www.zooniverse.org/projects/rainforestexpeditions/amazoncam-tambopata

Snapshot Serengeti: https://www.snapshotserengeti.org/

Please check the following researchgate links.

https://www.researchgate.net/project/Primate-Conservation

https://www.researchgate.net/project/Global-Patterns-of-Primate-Conservation

Those are great suggestions, thanks, Crystal and Arvind! I am focusing on primates for now. More specifically, I am interested in how the bird watching model could be applied to primates.

In case anyone else is interested, I have found another primate citizen science project since I posted the question: the Urban Slender Lorises of Bangalore (http://www.urbanslenderlorisproject.org/). Here there is a webinar video explaining the project: https://www.youtube.com/watch?v=sGqN_eMTXg8

Hello Fabiana, we are appliying the watching monkeys here in Brazil. If I can help you let me know. 

Hi Mariana! I would be curious to learn more about it!

Hello Fabiana, I just saw your answer. If you still interested send me an email. It will be more efficient.

Yes , here in Panama we have a citizen scientists cooperation, see fcprimatespanama.org